The present invention relates to the electrochemical arts. It finds particular application in conjunction with an electrode material for electrosynthesis and analysis and will be described with particular reference thereto. It should be appreciated, however, that the invention is also applicable to a variety of applications where electrical conductivity or chemical selectivity are desired.
Electrodes formed from electrically conductive diamond have been used in a number of applications. The diamonds are commonly of two types, namely, implanted diamonds having their surface conductivity from damage-generated sp2 (graphitic) content and chemically-vapor deposited boron-doped thin p-type diamond films of virtually metallic conductivity produced at high substrate temperatures.
The latter films have shown a wide electrochemical window for aqueous systems combined with the chemical resistance properties of diamond. The boron-doped diamond films, however, require high temperatures for their formation (typically 1175 K) and relatively small coating areas are presently available. Additionally, no significant degree of electrocatalytic activity is shown by the hydrogen terminated, inert surface of the boron-doped films, which makes all but outer-sphere electron transfer slow.
The present invention provides a new and improved electrode which overcomes the above-referenced problems and others.
In accordance with one aspect of the present invention, an electrochemical system is provided. The system includes an electrode comprising a substrate, and a layer of a material on the substrate, the layer consisting essentially of carbon incorporating nitrogen. The system also includes an electrolyte and a counter electrode.
In accordance with another aspect of the present invention, a method of electrochemical synthesis of a product of a redox reaction is provided. The method includes providing an electrode from a layer of a material consisting essentially of carbon incorporating nitrogen and inserting the electrode in an aqueous solution in which the redox reaction takes place. The method further includes passing an electric charge through the electrode.
In accordance with another aspect of the present invention, a method of forming an electrochemical system is provided. The method includes forming an electrode from a substrate with a layer of a nitrogen-containing amorphous carbon thereon and separating the electrode and a counter electrode with an electrolyte.
In accordance with another aspect of the present invention, a method of detecting a product of a chemical reaction is provided. The method includes providing a sensor with a wide electrochemical window between hydrogen and oxygen evolution potentials, the sensor including a carbon and nitrogen amorphous layer. The method further includes measuring a flow of current at a potential within the electrochemical window, the potential selected to correspond to a potential at which the chemical reaction takes place and determining a concentration of the product from the current measured.
One advantage of the present invention is that electrode material may be prepared at ambient temperatures.
Another advantage of the present invention is the provision of a sensor which has a wide potential window.
Another advantage of the present invention is the provision of an electrode which exhibits reversible behavior with outer sphere couples.
Another advantage of the present invention is the provision of a sensor which combines high catalytic ability with a high durability.
Still further advantages of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the preferred embodiments.